i got a bunch of xenia form fellow reefers, pom pom, elongata, and some anthillia sp too. all the pom pom and anthillia died during a temp spike, but i still have a lot of the elongata. i had one piecenear the bottom that had spread up and grew over my zoas, killing them because it was actualy on top of some. so i removed that. but when it split, another piece went the other way towards my sps. until a few horus ago, i had a digitata that was the only thing to survive an infestation to monti eating nudibranchs comply encased in xenia. i pulled up about 6 stalks, all withing 2-3 inches of it (but all the stalks were about 3-4 icnhes long) i had removed them not because they were causeing damage (the digi has since colored up and grown a lot since the infestation), but because i was cleaning the spot to place my new superman frag there. The xenia did absolutly no harm. of course though we shall see if the digi grows faster, or colors up even more now without them. but it was constatnly in contact with it with nothing wrong.